Proam creates negative extrusion cells if away from origin
 

Why does the mesh have to be near the origin to create the extrusion layer? I have done a few meshes where they are away from the origin and everytime a few cells in the extrusion layer will be negative. If I move the mesh near the origin (0,0,0), then my extrusion layer comes out great with no negative volumes.

Just scale you mesh from meter to mm (vset all $ vsca vset ,,, 1000 1000 1000).